Maven plugin and ANT tasks: Allow user and role definitions as XML tags

Description

Currently users and their roles are defined as configuration property.This approach has several disadvantages as it restrict possible values - they cannot contain : and | due to parsing - and it also complicates adding new users to configuration which has already some users defined - for example if we have maven profile with additional users.

Solution could be to create tags for defining users and their roles in maven plugin and add user list to LocalConfiguration which will be filled by current configuration property and new maven tags. This would also need refactoring of all containers which currently retrieve users by configuration property to use this new user list (it can bring small risk of regression for containers which aren't tested in automation). Or possible approach would be to implement this just for some containers, which are covered by tests, rest of containers would still rely just on configuration property.